all of you got it right...
we call out 80 kts for all those reasons, instrument x-check, possible incapacitation (or wake up call for those taking off on autopilot) and beggining of the high speed regime of take off run. We also call out, throttle hold.
Once we´ve said that the pf says "cross checked" meaning he took a look at his a/s indicator, fma, and stby a/s indicator. I believe the response is very important...wouldn´t be comfortable with an SOP calling for a response not necessary.